Retarded release-valve device



l 1,633,777 c. c. FARMER RETARDED RELEASE vALvE DEVICE Ju nef 28 1927.

Filed Sept. 8, 1925 l \l\\ 6 %/////,,W//// INVENTOR CLYDE QFARMERATTORNEY Patented June 28, 1927.

"UNITED STATES-- v 1,633,777 PATENT OFFICE,

CLYDE c. FARMER, 0E rrTTsBUReH, PENNSYLVANIA, ASSIGNOR To THE WESTING-HOUSE AIR BRAKE COMPANY, or WILMEBDING, PENNSYLVANIA, A conrona- TION OFPENNSYLVANIA.

' RETARDED RELEASE-VALVE nEvIcE,

Application filed September 8, 1925. Serial No. 54,88 7.

This invention relates to fluid pressure brakes and more particularly toa triple valve device.

When triple valve devices are being operart-ed in service,itoccasionally happens that the triple valve piston becomes cooked inthe piston cylinder, thereby causing 't'aulty operation of the triplevalve device.

One object of my invention is to obviate the above. difficulty byproviding an improved guiding means for the piston.

Where my improved piston guide is employed in connection with a triplevalve device of the retarded release type, the usual retarded releasestop. would interfere with the installation of the guide and therefore afurther object of my invention is to provide a retarded release stopadapted to be employed with the improved piston guide.

In the accompanying drawing; Fig. 1 is a vertical section of a triplevalve device embodying my invention; Fig. 2 a partial transverse sectionof the triple valve device showing the improved retarded release stopdevice; and Fig. 3 a side elevation of the retarded release stop device.I

As shown in the drawing, the triple valve device may comprise a casing 1having a piston chamber 2 containing a piston 3, which is adapted tooperate main slide valve 5 and graduating slide valve 6 through stem 4,said valves being disposed in slide valve bushing 7, which is fitted incasing 1.

According to my invention, the casing 1 is provided with an opening atone end adapted to be closed by a plug 8 having screwthreaded engagementwith the casing 1. The plug 8 is provided with an inwardly extendingportion 9 having a central bore 10 in accurate alinement with the pistoncylinder 2. The piston stem 1 is provided with a rearwardly extendingcylindrical guide portion 22, which is adapted to engage and have a neatsliding fit in the bore 10. I

In order to provide for retarded release, a retarded release stop isemployed, comprising a tubular member 11 adapted to be applied over theguide portion 22 and having an outwardly flaring flange 12 at one endadapted to engage the end of the slide valve bushing 7, and an inwardlyextending flange 13 spaced from the other end and adapted to engage acollar 1 1 on piston stem 4:-

bushing 7 so as to prevent rotation or" the member 11.

In order to yieldingly maintain the member 11 in its normal full releaseposition, a coil spring 20 is interposed between the flange 13 and theplug 8.

When fluid under pressure on opposite sides of piston 3 is equalized,said piston and consequently slide valves 5 and 6' are maintained in thenormal full release position, as shown in Fig. 1 of the drawing.

After the brakes have been applied in theusual manner, it it is desiredto release the brakes, the brake pipe pressure is increased. At the headend of the train where the increase in brake pipe pressure is at a rapidrate, the triple valve piston 3 is shifted to its innermost or retardedrelease position, moving the release stop member rearwardly against theresistance of spring 20. At the rear of the train, where the rate ofincrease in brake pipe pressure is less than at the head end, the triplevalve piston will only move to full release position, in which the slidevalve 5 engages the retarded release stop 11.

The provision of the extended guide mem ber 22 in connection with thetriple valve piston stem 4, serves to prevent cocking or" the triplevalve piston, and where employed with a retarded release triple valvedevice, I have provided a release stop adapted to be applied inconnection with the guide member.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is

1. A triple valve device comprising a casing having apiston chamber anda valve chamber, a piston in said piston chamber, a slide valve mountedin said valve chamber, a piston stem carried by said piston foroperating said Valve, a guide member extending rearwardly of said stem,a collar disposed between said stem and said extenlease stop devicecomprising a movable sion, and a tubular stop member engaging tubularmember engaging said valve, and a said valve and having a flangeengaging spring for opposing movement of said mem- 10 said collar. ber.

o 2. The combination with a triple valve In testimony whereof I havehereunto set device having a piston and a slide valve my hand. operableby said piston, of a; retarded re- 3 CLYDE C. FARMER.

